Compression arrangement



May 27, 1958 o. H. scHELDoRF 2,836,349

coMPREssIoN ARRANGEMEN'T Filed July 1s. 1953 'g His Attor-hefg.

United States Patent coMPnassroN ARRANGEMENT Owen H. Scheldorf, North East, Pa., assigner to General Electric Company, a corporation of New York Application July 13, 1953, Serial No. 367,471 4 claims. (ci. 23e-zes) My invention relates to refrigeration apparatus and pertains more particularly to the compressors in refrigcrating units. l

in constructing a refrigerating unit it is desirable to provide means for insuring satisfactory lubrication of the compressor thereof and minimizing compressor operating noise. Accordingly, the primary object of my invention is to provide in a refrigerating unit new and improved means for lubricating the compressor thereof and minimizing compressor operating noise.

Another object of my invention is to provide in a refrigerating unit new and improved means for metering oil into the compressor thereof.

Another object of my invention is to provide in a ret'rigerating unit new and improved means for admitting oil into the compressor thereof in such a state as to facilitate the distribution of the oil in the compressor.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed tol and forming part of this speciication.

In carrying out the objects of my invention, l provide a refrigerating unit comprising a gas containing case and a compressor adapted for being operated in the case. Provided in the compressor. is means for metering oil into an orifice for admission into and distribution in the compressor. Also provided is means for admitting gas into the orifice from the case when during operation ofthe compresor the pressure of ythe gas beyond the orice is less than in the case thereby to effect spraying of the oil metered into the orifice, into the compressor mechanism.

Por a better understanding of my invention, reference tay be had to the accompanying drawing in which:

Fig. l is a fragmentary sectional and partially schematic view of a refrigerating unit including a Scotch yoke compressor; l

Fig. 2 is an enlarged fragmentary sectional view taken along the line 2 2 in Fig. l and looking in the direction or" the arrows;

Fig. 3 is an enlarged fragmentary sectional view of a modified form of my invention;

Fig. 4 is an enlarged fragmentary sectional View of another modified form of my invention; l

5 is a fragmentary sectional view of the modification of Fig. 4 in whichV the cross slide is shown in a particular operating position;

A Fig. 6 is Va sectionalv view taken along the line 6 6 in Fig. 5 and looking in the direction of the arrows;

Fig-7 isan enlarged fragmentary sectional view illustrating still another modicationof my invention.

AReferring toig. l,-i have shown a refrigerating unit generally designated 1.V ,.Therefrigerating unit 1 comprisesV a caser shown in outline and indicated byQZ. The

case'Z is adapted for having the suction line Vof a refrig` erating system (not connected thereto whereby the case is lled with vaporous refrigerant or gas at suction pressure. Enclosed in the case 2 is a compressor generally designated 3 and a motor for driving the compressor generally designated 4.

Provided for supporting the compressor 3 and the motor 4 and suitably supported in the case is a frame 5. The frame S is cuplike in conguration and is secured at its edge to the stator laminations 6 of the motor 4. included in the motor and adapted for rotating in the stator laminations 6 is a rotor 7. suitably fitted in the rotor for being rotated thereby is a drive shaft E. The drive shaft 8 is suitably supported for rotation in a bearing sleeve 9 which extends through and is secured, as by welding, to the frame 5. On its outer extremity the drive shaft 3 is formed to include a shoulder. Formed on the shoulder and eccentrically disposed relative to the axis of the drive shaft S is a crank pin 10. Also carried on the shoulder for balancing the shaft is a counterweight 11. During rotation of the drive shaft the crank pin 10 rotates in a circular path for operating the compressor 3 which is of the Scotch yoke type.

The compressor 3 comprises a cylinder 12 anda piston 13 adapted for being operated in the cylinder by the crank pin lil. The cylinder 12 is secured, as by welding and brazing, to the edge of a suitable aperture formed in the horizontal leg 14- of an inverted L-shaped bracket 1S. The vertical leg 16 of the bracket 15 is secured, also as by welding and brazing, to the frame 5. Thus the cylinder is suitably supported for having the piston 13 operated therein.

Closing the upper end of the cylinder 12 and suitably secured to the upper side of the horizontal leg 14 of the bracket 15 is a cylinder head 17. The cylinder head 17 is formed to include an annular exhaust chamber 18. Carried by the cylinder head 17 is an exhaust valve 19. The exhaust valve 19 is a ilexible disk which is centrally secured to the cylinder head and adapted for cooperating at its outer edge with the upper edge of the cylinder l2 which in effect is a valve seat and is designated 2l?. This arrangement controls communication between the cylinder and the exhaust passage 18 in accordance with the pressure in the cylinder 12.

The piston 13 is cup-like or hollow and includes a head element 21 formed to include a plurality of intake passages or apertures 22. Carried on the head 21 and adapted for controlling communication between the cylinder 12 and the piston 13, or in other words between the interior of the piston and a compression chamber 23 formed through the cooperation of the piston and the cylinder, is an intake valve 24. The intake valve 24 is a. flexible disk which is centrally secured to the element 21 and adapted for cooperating at its outer edge with the apertures 22 to control ow of gas from the piston into the compression chamber 23 in accordance with the pre-ssure difference therebetween.

The piston 13 is adapted for receiving gas to be compressed through a lateral aperture 2S. The aperture 25 is adapted for registering with a gas inlet chamber 26 formed in the side of the cylinder 12 and to which is connected an inlet tube 27. The tube 27 connects with mufer 28 which is in open communication with the interior of the case 2 for receiving gas from the case and supplying it to the inlet chamber 26.

In the arrangement described to this point, reciprocation of the piston 13 in the cylinder 12 results at a predetermined point of reciprocation or on the dowustroke in a reduction of pressure in the compression chamber 23 and the piston 13. At this point the valve 24 opens the apertures 22 in the element 21 and the aperture 25 moves into register with the inlet chamber 26. rillus, vaporous refrigerant from the case is admitted into the compression chamber for being compressed.

. On the upstroke of the'pisrton the gasrin the compression chamber 23 is compressed whereby it is effective for maintaining the valve 24 seated for closing the-passages 22,

Subsequently, and at a predetermined degree of compression the gas in the'compression chamber 23 is etfectiveforY raising theexhaust valve 19 from the edge ofV the `cylinder or valve seat 2t) thereby to'permit the compressed gas to exit into the annular chamber 1S. By a connection, not shown, the compressed gas is conducted Vfrom the annular chamber 18 to a portion of the mufier 28Y adapted for muing exhaust noises. Means, also not Y fshown, is provided for conducting the exhaust gas from Y. shoulder of therdrive shaft and better seenin Fig, 2 Vis a horizontally elongated aperture 30. The aperture 3%Y permits extension into the yoke of the crankppin 10 and horizontal movement of the crank pin in the yoke; Provided for reciprocating in the yoke .29 is a cross slide '31. VThe cross slide'31` is formed to include a ytransverse bore 32 adapted for having the crank pin 10 rotatably ttedY therein. In this'arrangement circular travel or rotation of VVthe Y'crank pin 1i) as effected by rotation of theY drive shaft V8 results in `reciprocation of the cross slide 31 in in the manner indicated by 41 in Fig. V2.

r 1 r l .the drive shaft, and specific lly at bottom deadenter of the piston. It will be seen that, if desired, metering could take place twice or at both top and bottom dead center simply by extending the bore 39 through the crank pin 10.

It has been my further nding thatby injecting or spraying the oil metered into the orifice into the pistonV it is introduced into the piston in a state which facilitates Y its satisfactory conveyance into the compression chamber v by gas llowing through the piston and its more equalA distribution on the Walls of the chamber and the'valves resulting in more satisfactory lubrication andr'greater noise reduction. To Vaccomplish, thisjspraying of the metered koil into the piston, YI provide meansfor Vprovid-- ing communication between the piston fand the case through the orifice during that timetin the operation of the compressor when theY pressure in the piston is less than the pressure of gas in the case. This,fitrwill be seen, results in admission of gas into the piston directly from the case and through the oil-lled 'orifice whereby the oil inthe orice is injected or sprayed into the piston In the preferred form ofmy invention, the communiv cation between the piston and thercase through the orifice f is provided by a passage frormed by the cooperation of the cross slide and a groove 42 formed inY the Vinner pe,-A

Yriphery of the yoke and extending from the orice k38 Y to the edge of the elongatedV aperture in the yoke.

the'yokel9 and reciprocation or operation of the piston 13,in the cylinder 172. Y

Formed in the crank pin ltlis a passage 33. By pump- Y. Ying means, not shown, the passage 33 is adapted for being maintainedsupplied with oil drawn through a'tube3'4 from a reserve 35 thereofy in the sump of the case 2. Communicating. with the passage 33 and alsoV adapted for being maintained supplied with oil is a passage36'. In

' the preferred form of my invention, the passage 36 is formed byfa portion of the bore 32 Yand surface grooves 3.7 formed Vin the cross Vslide and cooperating with the inner or bearing surface of the .yoke 29..V rThe grooves 37 extend transversely from the bore 32k and terminate j A short of the aperture 30. This'arrangement provides for lubrication of the bearing surfacesfof the cross slide and yoke. Additionally/in a manner aboutto be described YAs pointed out above, vthe groove 37 Vis so disposed in the crossY slide 31 as to move into -Vregister with the orifice/38 for metering oil into the oriiice at both the top and bottomY dead centersof the piston stroke. And in the modified form ofrFig. 3 oil is metered into the orifice Y at bottom dead center. At approximately 90 of rotation of the drive shaft, regardlessof which ofthe described Ymetering arrangements is employed, the pressure Y Y in the piston 13 isA reducedv suciently for resultingin a flow of gas from the case intothe pistonY through the it assists in metering oilrinto Vthe compressor for` lubrica-l a tionand noise damping purposes. .Y

Y Providingfcommunication between the interiors of the t piston 13 and theV yoke 29. is means in the form Vof an v, orifice 38. :By this arrangement the oil supply passage 36 is moved into'and'out of register with the orifice 38 j `during*r'ecipro'cation of the cross slidein the lyoke for operating the pistonin the cylinder. Thus oil is metered into Vthe orifice forbeing conveyed into the compression chamberby gas ilowing through the piston into the coming Voil into the Y.piston and having it conveyed,V into theV pression, I am able to obtain Vsatisfactory* distribution f of oil inV theV compression chamber ffor lubrication Vand t Voil' damping of the lvalves 19 and24 to minimize valve operating noise. Y Y Y fIn'Fig; Sis illustrated ay modified formrorfmy invention 1 which vis identical .toi the above-described embodiment exceptgthat an alternative arrangement for metering oil Vintojthe compressor is provided; 'In this' alternativeV oil metering-'arrangement'abore 39 extends-from theoil paseV Vi,.sage*.rarinthre crank 'pin ,dito' the Vbearing surface of the Y crank'pin. Additionallwa similarbore eferitendsV radi? @allyV from theY transverse Yfbore 32 lingthe cross slide VY31 Y to the, be'aring'surface of thecrossMsliden'lnfthis arrange A. Y'Inentthe bores39 and 40 and the orifieenlvSrfarev aligned Y or registered for metering Voil intothe oricefor conduc- Vtion'into the compressoronceeach cycle or revolutionof Y VVpression chamber. It has Vbeen mytnding thatV by r'neter.-V

Y `and for the purpose Ibrought: Vout above'. `It willbbetseen that whleI have employed inthe modicationof Figs.; f4f6 the means employed inthe embodiment of Figs.

passage 42 and the orifice 38'for injectingY or spraying.V Y

the oil metered intov the orifice VintotheV piston. In its sprayed state as Vindicated by141theoil is moreY easily conveyed Vinto the compression chamber `by gas `passing throughthepiston.' Additionally, inthiss'tatethe oil is more Vequally distributable on the walls of'the'com-- pression chamberV 23 and the valves'A 19 and24, resultingV in more satisfactoryY lubrication and noise reduction.V Y

In Figs. 4-'6ris illustrated another Vmodied form of f my invention. This modication is identical to the pref Y Vfel-red form to the'extent that it includesv the passage 36 iformed by the groove 37 which Vis adapted forbeing maintained supplied with oil and moving into and out' of register with therorice 38 forY metering oil thereintol.- Thismodication differs from the iirst'described formi-n that theY injecting or spraying of the oil metered into thev piston'is accomplished'rby forming a flat43 on 'the Y crossslide at one `end thereof. In Ythis arrangement, the

Voil is metered Wintothe orifice Yat Yboth top and `bottor'n l. .Y V.dead centers of the iston stroke also.- Add'tio Va dY Y' Y compression chamber by gas'admitted theremtororcom-Y p 1 muy n as perhaps best seen in Figs.'5 Vand Y6 at Yapproximately er past top dead centerf the hat 43 Ymove'sinto registerwith the orifice 38. Thus communication is provided -between the case 2 and the `interior' of Ythe pistonV 13 throughY the oriiceV 38. Atfthis point in the voperation of the Ypiston in the cylinder Vthe pressurein the piston is Y less than that in the'casek resulting in a ow ofgasv from n Y Ythe case intoY the' pistonthrough the passage aiorded by the dat 43 Yand the oriicev38 for effecting injectionor spraying of the oil previouslyy meteredintoY the oriice into the piston in the mannen indicated by 41,. ik In this 1 Ysprayed or injected state the conveyance of thefoil into the compression chamber 23 is facilitatedin the-manner completely l and 2V for metering oil into the orifice 38 the metering arrangement of Fig. 3 is alternatively employable.

In Fig. 7 is illustrated still another modification of my invention. It, like the modification ust described, is similar to the iirst described embodiment in all respects with the exception of the means for spraying the oil into the piston 13. In this arrangement the cross slide 31 is formed to include a bore 44 extending from an end of the cross slide to the periphery or bearing surface thereof. The extremity of the bore at the bearing surface of the cross slide is adapted for moving into and out of register with the orice 38. At approximately 90 past top dead center and at which point in the operation oi the piston the pressure therein is less than the pressure in the case 2, the bore 44 moves into register with the orifice 38. When the orifice 38 and bore 44 are in register in this manner, communication is provided -between the interior of the piston and the case through the orifice and gas is admitted thereby into the case for injecting or spraying into the piston oil previously metered into the orice 38 by movement of the oil passage 36 into and out of register with the oriiice 38. Again it will be seen that the oil metering arrangement of Fig. 3 is alternatively employable -for depositing metered quantities of oil into the orice 38 -for being sprayed into the piston.

It Will be seen that the flat 43 in the modication of Figs. 4-6 and the bore 44 in the modification of Fig. 7 are each replaceable by a groove (not shown) which can be formed in the cross slide 31 for admitting gas into the orice for spraying oil therein into the piston 13. The groove can be similar to the upper one of the grooves 37 and can extend :beyond the edge of the aperture 30 and be so located on the cross slide as to move into register with the orifice 38 at approximately 90 past top dead center for thereby providing communication between the case and piston to spray the metered oil into the piston.

While I have shown and described a specific embodiment of my invention, I do not desire my invention to be limited to the particular form shown and described and I intend by the appended claims to cover all such modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a refrigerating unit, a gas containing case, a compressor disposed in said case for operating therein, said compressor comprising a cylinder, a hollow piston for cooperating with said cylinder to provide a compression chamber, means for operating said piston in said cylinder in a reciprocating motion to provide compression of said gas on the forward stroke of said lpiston and suction on the return stroke of said piston, means for admitting gas to be compressed into said piston during said suction stroke of said piston, means for admitting said gas into said compression chamber from said piston during said suction stroke of said piston, an orice in said piston, means in said operating means for metering oil into said orice, and means in said operating means providing communcation between said piston and said case through said orice in said piston whereby during the suction stroke of said piston when :the pressure therein is less than the pressure of said gas in said case said oil in said orifice is sprayed into said piston.

2. In a refrigerating unit, a gas containing case, a Scotch yoke compressor disposed in said case for operating therein, said compressor comprising a cylinder, a hollow piston for cooperating with said cyiinder to provide a compression chamber, means for operating said piston in said cylinder in a reciprocating motion to provide compression of said gas on the forward stroke of said piston and suction on the return stroke of said piston, means for admitting gas to be compressed into said piston during said suction stroke of said piston, means for admitting said gas into said compression chamber from said piston during said suction stroke of said piston, said means for operating said piston including a yoke connected to said piston, a cross slide reciprocating in said yoke, a drive shaft having a crank pin journalled in said cross slide for rotational movement therein to cause reciprocation of said yoke and said piston, an oriiice in said piston providing communication between the interiors of said piston and said yoke, a passage formed in said cross slide, means supplying oil to said passage, said passage moving into and out of register with said orifice during reciprocation of said cross slide in said yoke whereby oil is metered into said orifice, and means providing communication between said piston and said case through said orifice in said piston whereby during the suction stroke of said piston when the pressure therein is less than the pressure of said gas in said case said oil in said oriice is sprayed into said piston.

3. In a refrigerating unit, a gas containing case, a Scotch yoke compressor disposed in said case for operating therein, said compressor comprising a cylinder, a hollow piston for cooperating with said cylinder to provide a compression chamber, means for operating said piston in said cylinder in a reciprocating motion to provide compression of said gas on the forward stroke of said piston and suction on the return stroke of said piston, means for admitting gas to be compressed into said piston during the suction stroke of said piston, means for admitting said gas into said compression chamber from said piston during the suction stroke of said piston, said means for operating said piston including a cylindrical yoke connected to said piston, a cylindrical cross slide reciprocating in said yoke, a drive shaft having a crank pin journalled in said cross slide for rotation therein to cause reciprocation of said yoke and said piston, an orice in said piston providing communication between the interiors of said piston and said yoke, a passage formed in said cross slide, means supplying oil to said passage, said passage moving into and out of register with said orifice during reciprocation of said cross slide in said yoke whereby oil is metered into said orifice, and a at formed on said cross slide, said fiat moving into register with said orifice and providing communication between said piston and said case through said oriiice in said piston whereby during operation of said piston on said suction stroke when pressure therein is less than the pressure of said gas in said case said oil in said orifice is sprayed into said piston.

4. In a refrigerating unit, a gas containing case, a Scotch yoke compressor disposed in said case for operating therein, said compressor comprising a cylinder, a hollow piston for cooperating with said cylinder to provide a compression chamber, means for operating said piston in said cylinder in a reciprocating motion to provide compression of said gas on the forward stroke of said piston and suction on the return stroke of said piston, means for admitting gas to be compressed into said piston during the suction stroke of said piston, means for admitting said gas into said compression chamber from said piston during the suction stroke of said piston, said means for operating said piston including a yoke connected to said piston a cross slide reciprocating in said yoke, a drive shaft having a crank pin journalled in said cross slide for rotation therein to cause reciprocation of said yoke and said piston, an on'ce providing communication between the interiors of said piston and said yoke, a groove formed on the surface of said cross slide, means supplying oil to said groove, said groove moving into and out of register with said oriiice during reciprocation of said cross slide in said yoke whereby oil is metered into said oriiice, and a passageformed on said cross slide, said passage communicating at one end thereof with said gas within said case, said passage moving into register with said orifice and providing comthe pressurelrthereirn is less thanA the pressure; of *said K `2,031,024 Drysdale muniation between said piston and said cse; thi'oughV V1,922,092Y H1111 QQ A'ug.15v, 1933 said orce when during thessuctinstrokre of said pistn; ;1J9']4,421 Q fHaunzv; Y 'Sept. 25i1 9 34` gas njsaid'case wherebys'id oil in said'orice-is sprayedV intOE saidpiston.V ja@ 'Y Y A Y u 

